Is it more efficient to write a series of records on surface one and, when that

Question

Is it more efficient to write a series of records on surface one and, when that surface is full, to continue writing on surface two, and then surface three and so on? Or is it better to fill up every outside track of every surface before moving the heads inward to the next track position to continue writing?

1. Do a sketch/picture showing the problem in question.

2. Explain "in detail", your choice.

3. Include which one is faster, based on Seek, Search, Transfer.

This comes from chapter 7, any help on this is greatly appreciated.

Explanation / Answer

It's slower to fill a disk pack surface-by-surface than it is to fill it up track by trackand that leads us to a valuable concept. If we fill Track 0 of all of the surfaces, we've got a virtual cylinder of data. There are as many cylinders as there are tracks, and the cylinders are as tall as the disk pack. You could visualize the cylinders as a series of smaller and smaller soup cans, each nested inside the larger ones.

To access any given record, the system needs three things: its cylinder number, so the arm can move the read/write heads to it; its surface number, so the proper read/write head is activated; and its sector number.

One clarification: We've used the term surface in this discussion because it makes the concepts easier to understand. However, conventional literature generally uses the term track to identify both the surface and the concentric track. Therefore, our use of surface/track coincides with the term track or head used in some other texts

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